Note 1:

Under laboratory conditions, assuming power consumption at maximum limit for factory acceptance testing (0.8 mA for microprocessor in sleep mode, less than 0.05 mA for sonar/release section in sleep mode).

Note 2:

We recommend putting a safety margin in for the battery life. A very conservative approach would be half of the expected life time of the battery. You should also take the environment into consideration; you have a better chance of draining the battery in a very noisy harbor then you would in an open ocean.